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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Empowering the next generation: ANS’s newest book focuses on careers in nuclear energy
A new career guide for the nuclear energy industry is now available: The Nuclear Empowered Workforce by Earnestine Johnson. Drawing on more than 30 years of experience across 16 nuclear facilities, Johnson offers a practical, insightful look into some of the many career paths available in commercial nuclear power. To mark the release, Johnson sat down with Nuclear News for a wide-ranging conversation about her career, her motivation for writing the book, and her advice for the next generation of nuclear professionals.
When Johnson began her career at engineering services company Stone & Webster, she entered a field still reeling from the effects of the Three Mile Island incident in 1979, nearly 15 years earlier. Her hiring cohort was the first group of new engineering graduates the company had brought on since TMI, a reflection of the industry-wide pause in nuclear construction. Her first long-term assignment—at the Millstone site in Waterford, Conn., helping resolve design issues stemming from TMI—marked the beginning of a long and varied career that spanned positions across the country.
Jun-Yun Yang, Xiao Gang, Yang-Jun Ying
Nuclear Science and Engineering | Volume 182 | Number 4 | April 2016 | Pages 538-554
Technical Paper | doi.org/10.13182/NSE15-44
Articles are hosted by Taylor and Francis Online.
A code called CriSAA used for criticality excursion evaluation and analysis is developed by coupling a two-dimensional thermal-hydraulic code and a zero-dimensional neutron kinetics code. The generalized semi-Markov process simulation method is improved in the neutron kinetics code, which makes it suitable for the transient cases of both stochastic and intense neutron fields. Pulse withdrawal experiments and ramp feed experiments performed on the Transient Experiment Critical Facility (TRACY) are simulated with CriSAA. The transient characteristics of isolated and open criticality excursions on TRACY are studied. The simulation fits well with the experiments. Stochastic phenomena of the criticality excursions under a weak source case are studied. The statistics characteristics, including time and energy to first peak, power of first peak, and total energy, are shown. This work provides an advanced approach for criticality excursion evaluation and analysis.
